' ==============================================================================
'
'   File...... 24LC32.BSP
'   Purpose... 24LC32 control via I2C
'   Author.... Jon Williams
'   E-mail.... jwilliams@parallax.com
'   Started... 21 MAR 2002
'   Updated... 25 MAR 2002
'
'   {$STAMP BS2p}
'   {$PBASIC 2.5}
'
' ==============================================================================


' ------------------------------------------------------------------------------
' Program Description
' ------------------------------------------------------------------------------
'
' This program demonstrates essential I2C routines and communication with the
' Microchip 24LC32 serial EEPROM.


' ------------------------------------------------------------------------------
' Revision History
' ------------------------------------------------------------------------------


' ------------------------------------------------------------------------------
' I/O Definitions
' ------------------------------------------------------------------------------
'
SDA             PIN     8                       ' I2C serial data line


' ------------------------------------------------------------------------------
' Constants
' ------------------------------------------------------------------------------

DevType         CON     %1010 << 4              ' device type
DevAddr         CON     %000 << 1               ' address = %000 -> %111
EE2432          CON     DevType | DevAddr	' combine type and address

Ack             CON     0                       ' acknowledge bit
Nak             CON     1                       ' no ack bit


' ------------------------------------------------------------------------------
' Variables
' ------------------------------------------------------------------------------

eeAddr          VAR     Word                    ' address: 0 - 4095
test            VAR     Nib
outVal          VAR     Byte                    ' output to EEPROM
inVal           VAR     Byte                    ' input from EEPROM


' ------------------------------------------------------------------------------
' EEPROM Data
' ------------------------------------------------------------------------------


' ------------------------------------------------------------------------------
' Initialization
' ------------------------------------------------------------------------------

Initialize:
  DEBUG CLS,
        "24LC32 Demo", CR, CR,             ' setup output screen
        "Address... ", CR,
        "Output.... ", CR,
        "Input..... ", CR


' ------------------------------------------------------------------------------
' Program Code
' ------------------------------------------------------------------------------

Main:
  FOR eeAddr = 0 TO 4095
    DEBUG CRSRXY, 11, 2, DEC eeAddr, "   "
    FOR test = 0 TO 3
      LOOKUP test, [$FF, $AA, $55, $00], outVal
      DEBUG CRSRXY, 11, 3, IHEX2 outVal
      I2COUT SDA, EE2432, eeAddr.BYTE1\eeAddr.BYTE0, [outVal]
      PAUSE 10
      I2CIN SDA, EE2432, eeAddr.BYTE1\eeAddr.BYTE0, [inVal]
      DEBUG CRSRXY, 11, 4, IHEX2 inVal, "  "
      IF (inVal = outVal) THEN
        DEBUG "Pass  "
      ELSE
        DEBUG "Fail  "
      ENDIF
      PAUSE 40
    NEXT
  NEXT

  END 